JP3692058B2 - Vehicle shift control device - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a transmission control device for a vehicle, and more particularly to engagement force control of a friction engagement device during upshifting.
[0002]
[Prior art]
An automatic transmission in which a plurality of gear stages having different gear ratios according to the engagement and disengagement states of a plurality of friction engagement devices is widely used. The gear stage of such an automatic transmission is automatically switched in accordance with a shift condition (shift map or the like) having parameters such as an accelerator operation amount and a vehicle speed. For example, as shown in FIG. Throttle valve opening θ_THAs the value (corresponding to the accelerator operation amount) becomes smaller, the gear position on the high speed side with a smaller gear ratio is switched. When an upshift is performed in which a predetermined friction engagement device is engaged to shift to a high speed gear with a small gear ratio, the rotation of the driving force source is controlled by appropriately controlling the engagement force of the friction engagement device. It has been proposed to prevent shift shocks such as abnormal blowing up and shorten the shift time. For example, Japanese Patent Laid-Open No. 10-331963 discloses learning correction of an initial hydraulic pressure value (initial engagement force) at the start of a shift based on an input rotational speed change at the initial stage of an inertia phase, and an oil pressure based on the occurrence time of a blow abnormality. A technique for learning and correcting the preceding injection time (backlash filling time) is described.
[0003]
[Problems to be solved by the invention]
However, even if the engagement force and the like at the beginning of the shift are learned and corrected in this way, there is a possibility that a shift shock such as a change in driving force may occur due to a sudden engagement at the end of the shift where the friction engagement device is completely engaged.
[0004]
The present invention has been made against the background of the above circumstances, and an object of the present invention is to prevent a shift shock from occurring due to a sudden engagement of a friction engagement device at the end of an upshift. .
[0005]
[Means for Solving the Problems]
  In order to achieve such an object, the first invention includes: (a) an automatic transmission in which a plurality of gear stages having different gear ratios according to the engagement and disengagement states of the friction engagement device are established; In a vehicle transmission control device having an engagement force control means for controlling the engagement force of the friction engagement device at the time of an upshift in which the friction engagement device is engaged to shift to a gear stage having a small gear ratio, c)Initial engagement force learning correction means for changing the initial engagement force of the friction engagement device controlled by the engagement force control means at the start of shifting of the upshift based on an actual shift state; (d)Engagement force intermediate correction means for correcting the engagement force of the friction engagement device controlled by the engagement force control means during a shift in which the change in the input rotation speed in the inertia phase of the upshift has progressed by 50% or more;(e) The learning permission condition is that the change of the initial engagement force by the initial engagement force learning correction means is in a converged state,And an intermediate correction learning correction unit that changes an intermediate correction value, which is a correction amount of the engagement force by the engagement force intermediate correction unit, or a duration of the correction based on an actual shift state.
[0006]
According to a second aspect of the present invention, in the vehicle shift control apparatus according to the first aspect, the intermediate correction learning correction unit is based on a change in the input rotational speed of the automatic transmission after the correction by the engagement force intermediate correction unit and before the end of the shift. The intermediate correction value or the correction continuation time is changed.
[0008]
【The invention's effect】
  According to such a shift control device for a vehicle, the engagement force of the friction engagement device is corrected during the shift in which the change in the input rotation speed in the inertia phase of the upshift proceeds by 50% or more by the engagement force intermediate correction means. The intermediate correction value or the correction continuation time, which is the correction amount, is learned and corrected (changed) based on the actual shift state by the intermediate correction learning correction means, so that the input rotational speed change immediately before the end of the shift is appropriately controlled. It is possible to suppress the occurrence of a shift shock due to the sudden engagement of the friction engagement device at the end of the shift. In particular, since the intermediate correction value or correction duration time of the engagement force by the engagement force intermediate correction means is corrected by learning based on the actual shift state, the individual differences (variations) of various components, friction materials, lubricants, etc. Regardless of deterioration, the shift shock can be appropriately suppressed.
  On the other hand, since the initial engagement force at the start of upshifting is learned and corrected based on the actual shift state, this initial engagement force affects the overall shift state. Therefore, the learning correction of the intermediate correction value or the correction duration time is affected by the learning correction of the initial engagement force. It is possible to prevent the accuracy from being lost and hunting from occurring.
[0009]
In the second aspect of the invention, the intermediate correction value or the correction duration time is learned and corrected based on the input rotational speed change of the automatic transmission after the correction by the engaging force intermediate correction means and before the shift end. It is possible to more effectively suppress a shift shock such as a change in driving force at the time of complete engagement that is greatly affected by a change in rotational speed.
[0011]
DETAILED DESCRIPTION OF THE INVENTION
As an automatic transmission, for example, a planetary gear type automatic transmission including a plurality of planetary gear devices is widely known. As the friction engagement device, for example, a hydraulic friction engagement device that is engaged by a hydraulic actuator is preferably used. In this case, the engagement force is controlled by hydraulic control such as duty control of a linear solenoid valve. This can be done by directly controlling the supply hydraulic pressure or controlling the accumulator back pressure.
[0012]
The gear stage of the automatic transmission is automatically switched in accordance with, for example, a driver's required output amount (accelerator operation amount, throttle valve opening, etc.) and a speed change condition (shift map, etc.) using vehicle speed as parameters. Is determined to shift up when the vehicle speed decreases or the vehicle speed increases. The present invention is preferably applied to a power-ON upshift accompanying a vehicle speed increase during driving traveling in which power is transmitted from a driving force source to a wheel side, but an upshift caused by a driver's shift lever operation or the like It is also possible to apply to.
[0013]
As a driving force source, an internal combustion engine such as a gasoline engine or a diesel engine is preferably used. However, another driving force source such as an electric motor can be used, and torque between the automatic transmission and the automatic transmission can be used as necessary. A fluid transmission device such as a converter or a fluid coupling, or a starting clutch for connecting and disconnecting power transmission is provided.
[0014]
The engagement force control means is configured to feed forward control the engagement force, for example, the hydraulic pressure of the hydraulic friction engagement device, for example, according to a predetermined change pattern, but the input rotational speed of the automatic transmission changes a predetermined amount. Various engagement forces such as feedback control for increasing / decreasing the engagement force based on a speed deviation between the input rotation speed and the target rotation speed so as to change at a rate or according to a predetermined change pattern determined in advance Control is possible. In the case of feedback control, high control accuracy may not always be obtained due to response delay or the like, and intermediate correction is performed during shifting as in the present invention, and the correction amount is learned and reflected in the subsequent intermediate correction. It is effective.
[0015]
The present invention relates to the engagement force control of the frictional engagement device on the engagement side. In the case of clutch-to-clutch shift in which one of the pair of frictional engagement devices is released and the other is engaged, the release side is separately provided. The engagement force of the friction engagement device is controlled (including the case where it is released at once).
[0016]
  The engagement force intermediate correction means is, MaTo prevent shock when the frictional engagement device is fully engaged,In the inertia phaseShift progress (change in input rotation speed) is 50% or moreso,Furthermore, it is desirable to correct when 70% or more has passed.
[0017]
The intermediate correction learning correction means desirably learns and corrects the intermediate correction value, but it is also possible to change the correction continuation time of the intermediate correction (learning correction) so as to obtain a predetermined shift state. Both the intermediate correction value and the correction duration time can be corrected by learning.
[0018]
The intermediate correction learning correction means learns and corrects the intermediate correction value or the correction duration based on the input rotational speed change of the automatic transmission after the correction by the engaging force intermediate correction means and before the end of the shift as in the second invention. However, it is also possible to perform learning correction using parameters other than the input rotational speed change, such as the presence or absence and degree of torque fluctuation at the end of shifting. Since the input rotational speed substantially corresponds to the driving force source rotational speed, the driving force source rotational speed can be used instead of the input rotational speed if it does not matter. The same applies to other controls.
[0019]
  FirstThe initial engagement force learning correction means is configured to learn and correct the initial engagement force, for example, based on a change in the input rotational speed of the automatic transmission after the start of shifting and before correction by the engagement force intermediate correction means. However, learning correction can also be performed using other parameters.
[0020]
The intermediate correction learning correction means and the initial engagement force learning correction means may increase or decrease the intermediate correction value, the correction duration, or the initial engagement force by a predetermined fixed amount, but a predetermined control amount that changes due to the learning correction. Various modes can be employed, such as a method of obtaining a change amount according to a deviation between the target value and the target value. Whether the learning correction is in the convergence state can be determined, for example, based on whether the amount of change within a predetermined time is equal to or less than a predetermined value or whether the deviation between the control amount and the target value is equal to or less than a predetermined value.
[0021]
【Example】
Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
FIG. 1 is a skeleton diagram of a horizontally installed vehicle drive device such as an FF (front engine / front drive) vehicle. The output of an engine 10 such as a gasoline engine includes a torque converter 12, an automatic transmission 14, a differential gear. It is transmitted to a driving wheel (front wheel) (not shown) via the device 16. The torque converter 12 includes a pump impeller 20 connected to the crankshaft 18 of the engine 10, a turbine impeller 24 connected to the input shaft 22 of the automatic transmission 14, and a non-rotating member via a one-way clutch 26. A stator 30 fixed to the housing 28 and a lockup clutch 32 connected to the input shaft 22 via a damper (not shown). The engine 10 is a driving force source, and the torque converter 12 is a fluid transmission.
[0022]
The automatic transmission 14 is coaxially disposed on the input shaft 22 and a carrier and a ring gear are connected to each other to thereby form a so-called CR-CR coupled planetary gear mechanism. A first planetary gear unit 40 and a second planetary gear unit 42; a set of third planetary gear units 46 arranged coaxially on a counter shaft 44 parallel to the input shaft 22; and a shaft end of the counter shaft 44 An output gear 48 that is fixed and meshes with the differential gear device 16 is provided. The components of the planetary gear devices 40, 42, 46, that is, the sun gear, the ring gear, and the carrier that rotatably supports the planet gears meshing with them are selectively connected to each other by four clutches C0, C1, C2, C3, Alternatively, the three brakes B1, B2, and B3 are selectively connected to the housing 28 that is a non-rotating member. The two one-way clutches F1 and F2 are engaged with each other or with the housing 28 depending on the rotation direction. Since the differential gear device 16 is configured symmetrically with respect to the axis (axle), the lower side is not shown.
[0023]
The first planetary gear device 40, the second planetary gear device 42, the clutches C0, C1, C2, the brakes B1, B2, and the one-way clutch F1 arranged coaxially with the input shaft 22 are moved forward and reverse in four steps. A one-stage main transmission unit MG is configured, and a set of planetary gear unit 46, clutch C3, brake B3, and one-way clutch F2 arranged on the counter shaft 44 constitute a sub-transmission unit, that is, an underdrive unit U / D. It is configured. In the main transmission unit MG, the input shaft 22 is connected to the carrier K2 of the second planetary gear unit 42, the sun gear S1 of the first planetary gear unit 40, and the sun gear S2 of the second planetary gear unit 42 via the clutches C0, C1, and C2. Each is connected. The ring gear R1 of the first planetary gear unit 40 and the carrier K2 of the second planetary gear unit 42 are connected, and the ring gear R2 of the second planetary gear unit 42 and the carrier K1 of the first planetary gear unit 40 are connected to each other. The sun gear S2 of the second planetary gear unit 42 is connected to the housing 28 that is a non-rotating member via a brake B1, and the ring gear R1 of the first planetary gear unit 40 is a housing 28 that is a non-rotating member via a brake B2. It is connected to. A one-way clutch F1 is provided between the carrier K2 of the second planetary gear unit 42 and the housing 28 which is a non-rotating member. The first counter gear G1 fixed to the carrier K1 of the first planetary gear device 40 and the second counter gear G2 fixed to the ring gear R3 of the third planetary gear device 46 are meshed with each other. In the underdrive unit U / D, the carrier K3 and the sun gear S3 of the third planetary gear unit 46 are connected to each other via the clutch C3, and between the sun gear S3 and the housing 28 that is a non-rotating member, A brake B3 and a one-way clutch F2 are provided in parallel.
[0024]
The clutches C0, C1, C2, and C3 and the brakes B1, B2, and B3 (hereinafter simply referred to as the clutch C and the brake B unless otherwise distinguished) are controlled by a hydraulic actuator such as a multi-plate clutch or a band brake. In the hydraulic friction engagement device, the hydraulic circuit is driven by excitation, de-excitation, or a manual shift valve (not shown) of the linear solenoids SL1, SL2, SL3, SLT and solenoids DSL, S4, SR of the hydraulic control circuit 98 (see FIG. 3). By switching, for example, as shown in FIG. 2, the engaged / released state is switched, and the gear stages such as five forward speeds and one reverse speed are changed according to the operation position (position) of the shift lever 72 (see FIG. 3). It is established. “1st” to “5th” in FIG. 2 mean the first to fifth forward gears, “◯” means engagement, “×” means release, and “△” means only during driving. Means engagement. For example, according to the shift pattern shown in FIG. 4, the shift lever 72 includes a parking operation position “P”, a reverse travel operation position “R”, a neutral (power cut-off) position “N”, a forward travel operation position “D”, “ 4 ”,“ 3 ”,“ 2 ”,“ L ”, and the manual shift valve is mechanically connected to the shift lever 72, and mechanically according to the operation position. Are to be switched.
[0025]
In FIG. 2, for example, a 4 → 5 shift or a 5 → 4 shift between the 4th speed gear stage and the 5th speed gear stage is engaged with the clutch C3 and released the brake B3 under the action of the one-way clutch F2. 1 → 2 shift or 2 → 1 shift between the first gear and the second gear is achieved by engagement or disengagement of the brake B1. The However, the 2 → 3 shift or the 3 → 2 shift between the second gear and the third gear is performed by releasing the brake B1 and engaging the clutch C0, or releasing the clutch C0 and engaging the brake B1. Is a so-called clutch-to-clutch shift, and the 3 → 4 shift or the 4 → 3 shift between the third gear and the fourth gear is also performed by releasing the clutch C1 and engaging the brake B1. This is a so-called clutch-to-clutch shift achieved by releasing the brake B1 and engaging the clutch C1. Further, the downshift to the low speed side gear stage where the engine brake acts is a clutch-to-clutch shift.
[0026]
3 is a block diagram for explaining a control system provided in the vehicle for controlling the engine 10 and the automatic transmission 14 of FIG._CCIs detected by the accelerator operation amount sensor 51. The accelerator pedal 50 is largely depressed according to the driver's required output amount, and corresponds to an accelerator operation member._CCCorresponds to the required output amount. An accelerator pedal operation amount A is connected to the intake pipe of the engine 10 by a throttle actuator 54._CCOpening angle (opening) according to_THAn electronic throttle valve 56 is provided. An idle speed NE of the engine 10 is provided in a bypass passage 52 that bypasses the electronic throttle valve 56 for idle speed control._IDLIn order to control this, an ISC (idle rotational speed control) valve 53 for controlling the intake air amount when the electronic throttle valve 56 is fully closed is provided. In addition, an engine rotation speed sensor 58 for detecting the rotation speed NE of the engine 10, an intake air amount sensor 60 for detecting the intake air amount Q of the engine 10, and an intake air temperature T_AThe intake air temperature sensor 62 and the electronic throttle valve 56 are fully closed (idle state) and the opening θ thereof._TH, A throttle sensor 64 with an idle switch for detecting the rotational speed N of the counter shaft 44 corresponding to the vehicle speed V_OUTFor detecting the vehicle speed sensor 66 and the coolant temperature T of the engine 10_WThe coolant temperature sensor 68 for detecting the brake, the brake switch 70 for detecting the operation of the brake, and the shift position (operation position) P of the shift lever 72_SHShift position sensor 74 for detecting the turbine rotational speed NT (= the rotational speed N of the input shaft 22)_IN) For detecting the turbine rotation speed sensor 76 and the AT oil temperature T, which is the temperature of the hydraulic oil in the hydraulic control circuit 98._OILAre provided with an AT oil temperature sensor 78, a counter rotational speed sensor 80 for detecting the rotational speed NC of the first counter gear G1, and the like, and from these sensors, the engine rotational speed NE and the intake air amount are detected. Q, intake air temperature T_A, Throttle valve opening θ_TH, Vehicle speed V, engine coolant temperature T_W, Brake operating state BK, shift position 72 of shift lever 72_SH, Turbine rotation speed NT, AT oil temperature T_OILA signal representing the counter rotational speed NC or the like is supplied to the electronic control unit 90.
[0027]
The electronic control unit 90 includes a so-called microcomputer having a CPU, a RAM, a ROM, an input / output interface, and the like. The CPU uses a temporary storage function of the RAM, and signals according to a program stored in the ROM in advance. By performing the processing, the output control of the engine 10 and the shift control of the automatic transmission 14 are executed, and the engine control and the shift control are divided as necessary. As for the output control of the engine 10, in addition to controlling the opening and closing of the electronic throttle valve 56 by the throttle actuator 54, the fuel injection valve 92 is controlled for controlling the fuel injection amount, and the ignition device 94 such as an igniter is controlled for controlling the ignition timing. To control the ISC valve 53 for idle rotation speed control. The control of the electronic throttle valve 56 is performed, for example, from the relationship shown in FIG._CCThe throttle actuator 54 is driven based on the_CCIncreases as the throttle valve opening θ increases_THIncrease.
[0028]
As for the shift control of the automatic transmission 14, for example, the actual throttle valve opening θ from the shift map (shift condition) stored in advance shown in FIG._THFurther, the gear stage of the automatic transmission 14 is determined based on the vehicle speed V, and the solenoids DSL, S4, SR of the hydraulic control circuit 98 are turned on (excited) and turned off (de-energized) so as to establish the determined gear stage. Or the excitation states of the linear solenoids SL1, SL2, SL3, and SLT are continuously changed by duty control or the like. The linear solenoids SL1, SL2, and SL3 can directly control the engagement hydraulic pressures of the brake B1 and the clutches C0 and C1, respectively, and a shift shock such as a change in driving force occurs or the durability of the friction material is impaired. These oil pressures are regulated so that they do not occur. The solid line in FIG. 6 is the upshift line, and the broken line is the downshift line, and the vehicle speed V increases or the throttle valve opening θ_THThe gear ratio (= input rotation speed N_IN/ Output rotation speed N_OUT) Can be switched to a smaller gear on the high speed side. In the figure, “1” to “5” mean the first speed gear stage “1st” to the fifth speed gear stage “5th”.
[0029]
As shown in FIG. 7, the electronic control unit 90 also controls the engagement force of the friction engagement device on the engagement side at the time of power-on upshift when shifting to the high speed gear stage during driving of the vehicle. Each function of the control means 100, the initial engagement force learning correction means 112, and the intermediate correction value learning correction means 114 is provided. The upshift in which this engagement force control is performed is a 1 → 2 upshift and 3 → 4 upshift that engages the brake B1, and a 2 → 3 upshift that engages the clutch C0. The brake B1 and the clutch C0 are respectively Oil pressure P of the hydraulic actuator by duty control of the excitation current of the linear solenoids SL1 and SL2 of the hydraulic control circuit 98_B1, P_C0By adjusting the pressure, the engagement force is controlled.
[0030]
The engagement force control means 100 includes a backlash filling means 102, an initial engagement force control means 104, a first sweep means 106, an engagement force intermediate correction means 108, and a second sweep means 110. For example, in the time chart of FIG. As shown, the duty ratio DSL1 is feedforward controlled according to a predetermined change pattern. FIG. 9 shows the case of 3 → 4 upshift where the brake B1 is engaged, and the time t₁Is the time when the 3 → 4 upshift command is output, and the case of this 3 → 4 upshift will be specifically described below.
[0031]
When the 3 → 4 upshift command is output, the backlash filling means 102 first sets the duty ratio DSL1 to the backlash setting value DSL1._AThe hydraulic oil is rapidly filled into the hydraulic actuator within a range in which the brake B1 does not generate the engagement torque. In this embodiment, the hydraulic pressure P decreases as the duty ratio DSL1 decreases._B1Is going to rise.
[0032]
Subsequently, the initial engagement force control means 104 reads out the learning correction value gdupapl from the learning correction value data map 116, reads out the constant pressure standby pressure reference value upapl from the reference initial engagement force data map 118, and adds them to the constant pressure standby pressure control. Value DSL1_BBy returning the duty ratio DSL1 to the hydraulic pressure P_B1The constant pressure standby pressure control value DSL1_BTo a constant pressure standby pressure corresponding to. The learning correction value gdupap1 is stored in the learning correction value data map 116 using the turbine rotational speed NT at the time of, for example, a shift command output as a parameter, and the initial engagement force learning correction unit 112 performs engine blow based on the actual shift state. The learning is corrected sequentially so as not to cause a shift shock. Further, the constant pressure standby pressure reference value upapl is, for example, the type of shift or the AT oil temperature T_OIL, Vehicle speed V, turbine rotational speed NT, estimated input torque, and other operating conditions are stored in reference initial engagement force data map 118 as parameters. The learning correction value data map 116 and the reference initial engagement force data map 118 are stored in a data storage device 82 (see FIG. 3) such as an SRAM that can be appropriately rewritten and can retain stored contents even when the power is turned off. The constant pressure standby pressure control value DSL1_BCorresponds to the initial engagement force of the brake B1.
[0033]
The duty ratio DSL1 is the constant pressure standby pressure control value DSL1 by the initial engagement force control means 104 until the start of the inertia phase when the turbine rotational speed NT starts to change due to the frictional engagement of the brake B1._BWhen the inertia phase starts, the first sweep means 106 gradually decreases the predetermined sweep rate, and the oil pressure P increases with the change in the duty ratio DSL1._B1Is gradually increased. Whether the inertia phase has started is determined by the gear ratio of the gear before shifting (the third gear in FIG. 9) and the counter rotational speed NC or vehicle speed V (output rotational speed N)._OUT) Can be determined by comparing the front gear speed NTBF obtained from the above and the actual turbine speed NT. The sweep rate is set in advance in the sweep rate data map 124 using, for example, the turbine rotational speed NT at the time of a shift command output, the estimated input torque, and the like as parameters, and the sweep rate data map 124 is stored in the data storage device 82. ing. Time t in FIG.₂Is the start time of the inertia phase. Note that the duty ratio DSL1 = DSL1_BIf the inertia phase does not start even after a predetermined backup time has elapsed, the sweep of the duty ratio DSL1 is forcibly started by the first sweep means 106, and the learning correction is performed by a backup learning correction means (not shown). The learning correction value gdupap1 in the value data map 116 is updated so as to increase the constant pressure standby pressure.
[0034]
The engaging force intermediate correction means 108 reads out the learning correction value gupend from the learning correction value data map 120, reads out the reference correction value upend from the reference correction value data map 122, and adds the intermediate correction control value GD during the shift. By increasing the duty ratio DSL1 at a predetermined timing, the hydraulic pressure P_B1Is reduced by the hydraulic pressure (intermediate correction value) corresponding to the intermediate correction control value GD. The learning correction value gdupend is stored in the learning correction value data map 120 using, for example, the turbine rotation speed NT when a shift command is output as a parameter, and the intermediate correction value learning correction unit 114 completes the shift based on the actual shift state. Sequential learning correction is performed so that a shift shock such as output shaft torque fluctuation does not occur immediately. The intermediate correction value learning correction unit 114 corresponds to an intermediate correction learning correction unit. Further, the reference correction value “upend” is, for example, the type of shift or the AT oil temperature T_OIL, Vehicle speed V, turbine rotational speed NT, estimated input torque, and other operating conditions are stored in reference correction value data map 122 as parameters. The learning correction value data map 120 and the reference correction value data map 122 are stored in the data storage device 82. Time t in FIG._FourIs the time when the duty ratio DSL1 is corrected by the engagement force intermediate correction means.
[0035]
Thereafter, the duty ratio DSL1 is gradually decreased at a predetermined sweep rate by the second sweep means 110, and the hydraulic pressure P is changed with the change of the duty ratio DSL1._B1Is gradually increased, and when the shift of the brake B1 is completely engaged by the increase of the hydraulic pressure, the duty ratio DSL1 = 0 is set and the hydraulic pressure P is set._B1Is raised to the line pressure PL, and the brake B1 is stably held in the engaged state. The sweep rate at this time may be the same as that of the first sweep means 106, but can be increased or decreased by multiplying by a predetermined correction coefficient, or can be set independently using another sweep rate map. Anyway. Whether or not the shift is completed depends on the gear ratio of the gear stage after the shift (the fourth speed gear stage in FIG. 9) and the counter rotational speed NC or the vehicle speed V (output rotational speed N)._OUT) Can be determined based on whether or not the rear gear speed NTUP and the actual turbine speed NT are equal to each other. Time t in FIG.₆Is the shift end time.
[0036]
In this way, the duty ratio DSL1 is feedforward controlled according to a predetermined change pattern, whereby the hydraulic pressure P_B1Gradually increases, the brake B1 is frictionally engaged, and the turbine rotational speed NT is decreased, whereby a 3 → 4 shift is performed. In the clutch C1, which is a disengagement side frictional engagement device, the excitation current of the linear solenoid SL3 is duty controlled and the hydraulic pressure P_C1Is reduced so that engine blow and tie-up do not occur.
[0037]
FIG. 8 is a flowchart for explaining the specific contents of the signal processing of the engagement force intermediate correction means 108 and the intermediate correction value learning correction means 114. Steps S1 to S4 are executed by the engagement force intermediate correction means 108, and steps S5 to S5 are executed. S <b> 10 is executed by the intermediate correction value learning correction unit 114.
[0038]
In step S1 of FIG. 8, it is determined whether or not an upshift command has been output within the range up to the fourth gear, and when the upshift command is output, step S2 is executed to execute intermediate correction execution conditions. Judge whether to satisfy. The intermediate correction execution conditions are determined so as to satisfy all of the following conditions, for example.
(1) A single upshift.
(2) The vehicle is in a driving state. Specifically, the idle switch is OFF. (3) AT oil temperature T_OILIs a predetermined range.
(4) Engine water temperature T_WIs greater than or equal to a predetermined value.
(5) The turbine rotational speed NT is equal to or higher than a predetermined value.
(6) The start of the sweep by the first sweep means 106 is not due to the elapse of the backup time.
[0039]
If the intermediate correction execution condition is satisfied, it is determined in step S3 whether an intermediate correction start condition is satisfied. The intermediate correction start condition is that the speed deviation (NT-NTUP) between the turbine rotational speed NT and the rear gear stage rotational speed NTUP is less than or equal to a predetermined determination value α. In order to be able to determine that the vehicle has progressed about ˜80%, it is set by a data map, an arithmetic expression, or the like using parameters such as the turbine rotation speed NT at the time of a shift command output or the type of shift and the vehicle speed V. The progress of the shift can be defined, for example, by defining the difference in rotational speed between the front gear stage rotational speed NTBF and the rear gear stage rotational speed NTUP as 100%. When the intermediate correction start condition is satisfied, in step S4, the learning correction value gdupen is read from the learning correction value data map 120, the reference correction value upward is read from the reference correction value data map 122, and the intermediate correction is added. The hydraulic pressure P is increased by increasing the duty ratio DSL1 by the control value GD._B1Reduce. Time t in FIG._FourIs a time when the intermediate deviation is started when the speed deviation (NT−NTUP) ≦ α, and after continuing the duty ratio DSL1 for a predetermined time, the process proceeds to the sweep by the second sweep means 110. To do.
[0040]
In a succeeding step S5, it is determined whether or not an execution condition for the initial engagement force learning correction is satisfied. This is the initial engagement force, that is, the constant pressure standby pressure control value DSL1._BThis is because the learning correction of the intermediate correction value (intermediate correction control value GD) cannot be properly performed in the driving state where the learning correction is not properly performed. The execution condition of the initial engagement force learning correction is, for example, as follows: It is determined to satisfy all the conditions.
(1) A single upshift.
(2) Not the first upshift after the ignition switch is turned on.
(3) Not driving on a low μ road.
(4) AT oil temperature T_OILIs a predetermined range.
(5) The vehicle speed V is within a predetermined range.
(6) It is not at the time of changing the gear shift pattern at extremely low temperatures.
[0041]
If the execution condition for the initial engagement force learning correction is satisfied, the turbine rotational speed gradient ΔNT2 in the latter half of the shift is calculated according to the following equation (i) in step S6. ΔNT2 is the amount of change in turbine rotational speed NT per 150 msec._S2Is the time when measurement is started, that is, when the intermediate correction is started in this embodiment (time t in FIG. 9)._Four) Of the rotational speed between the turbine rotational speed NT and the front gear stage rotational speed NTBF, NT_E2Is at the end of measurement (time t in FIG._Five), The rotational speed difference between the turbine rotational speed NT and the front gear stage rotational speed NTBF, TΔNT2 is the time from the start of measurement to the end of measurement (time t in FIG. 9)._Five-T_Four) [Msec]. The measurement ends when the speed deviation (NT-NTUP) between the turbine rotational speed NT and the rear gear stage rotational speed NTUP is less than or equal to a predetermined determination value β. In order to be able to determine that the vehicle has traveled, it is set by a data map or an arithmetic expression using the turbine rotation speed NT at the time of a shift command output, or the type of shift or the vehicle speed V as a parameter. In this embodiment, the change in the turbine rotation speed NT corresponds to the change in the input rotation speed, and the turbine rotation speed gradient ΔNT2 is a parameter representing the shift state and is a control amount by learning correction.
ΔNT2 = [(NT_S2-NT_E2) / TΔNT2] × 150 (i)
[0042]
In the next step S7, it is determined whether or not a learning correction value calculation condition is satisfied. The learning correction value calculation conditions are determined so as to satisfy all of the following conditions, for example. These conditions are the initial engagement force (constant pressure standby pressure control value DSL1_BThis is because the learning correction of the intermediate correction value (intermediate correction control value GD) cannot be performed properly if the control of the initial engagement force is not stable.
(1) The learning correction by the initial engagement force learning correction means 112 has converged.
(2) The initial engagement force learning correction value gdupap1 is not backed up by learning correction.
[0043]
The above condition (1) is that, for example, the turbine rotation speed gradient ΔNT1 in the first half of the shift is a predetermined target value ΔNT1.^*Within ± 10% of the target value ΔNT1^*Is set so that a shift shock such as engine blow does not occur using, for example, the turbine rotational speed NT and the estimated input torque at the time of a shift command output as parameters. The initial engagement force learning correction means 112 is configured to output the turbine rotational speed gradient ΔNT1 and the target value ΔNT1.^*The learning correction value gdupap1 is changed in accordance with the deviation from the turbine rotational speed gradient ΔNT1 and the target value ΔNT1.^*If it is within ± 10%, the amount of change of the learning correction value gdupapl is small, and it can be said that the learning correction is in a converged state. The turbine rotation speed gradient ΔNT1 is the amount of change in the turbine rotation speed NT per 150 msec, and the constant engagement standby pressure control value DSL1 by the initial engagement force learning correction unit 112._BIs calculated according to the following equation (ii). NT_S1Is the time when the measurement starts, that is, when the inertia phase starts in this embodiment (time t in FIG. 9).₂The rotational speed difference between the turbine rotational speed NT and the front gear stage rotational speed NTBF is substantially 0, NT._E1Is at the end of measurement (time t in FIG._Three), The rotational speed difference between the turbine rotational speed NT and the front gear stage rotational speed NTBF, TΔNT1 is the time from the start of measurement to the end of measurement (time t in FIG. 9)._Three-T₂) [Msec]. The measurement is finished when the speed deviation (NT-NTUP) between the turbine rotational speed NT and the rear gear stage rotational speed NTUP is less than or equal to a predetermined judgment value γ. In order to be able to determine that the vehicle has traveled, it is set by a data map or an arithmetic expression using the turbine rotation speed NT at the time of a shift command output, or the type of shift or the vehicle speed V as a parameter. This determination value γ is larger than the determination value α.
ΔNT1 = [(NT_S1-NT_E1) / TΔNT1] × 150 (ii)
[0044]
If the determination in step S7 is YES (positive), that is, if the learning correction value calculation condition is satisfied, step S8 is executed, and the turbine rotation speed gradient ΔNT2 and a predetermined target value ΔNT2 are determined.^*A value obtained by multiplying the deviation by a predetermined gain (amount of change) is added to the original learning correction value gdupend to calculate a new learning correction value gdupend. Target value ΔNT2^*Is set such that, for example, the turbine rotation speed NT at the time of a shift command output and the estimated input torque are parameters, so that a shift shock does not occur due to a sudden engagement of the friction engagement device at the end of the shift. In step S9, the new learning correction value gdupend and the change amount thereof are limited by predetermined upper and lower limit guards, and in step S10, the learning correction value gdupenp of the corresponding part of the learning correction value data map 120 is rewritten. .
[0045]
The above description has been made centering on the 3 → 4 upshift, but the 1 → 2 upshift and the 2 → 3 upshift also apply the brake B1 which is the friction engagement device on the engagement side, and the hydraulic pressure P of the clutch C0._B1, P_C0While the duty ratios of the linear solenoids SL1 and SL2 that control the motor are changed in accordance with a predetermined change pattern, intermediate correction is performed in the middle of shifting, and the intermediate correction value (intermediate correction control value GD) or initial engagement force is used. The same hydraulic control as in the case of the 3 → 4 upshift is performed, for example, a certain constant pressure standby pressure control value is learned and corrected.
[0046]
Here, in the present embodiment, the engagement force of the friction engagement device on the engagement side is corrected during the upshift by the engagement force intermediate correction means 108, and the intermediate correction control value GD that is the correction amount is intermediate. Since the correction value learning correction means 114 sequentially learns corrections (changes) based on the actual shift state, it is possible to appropriately control the changing speed of the turbine rotational speed NT immediately before the end of the shift. It is possible to suppress the occurrence of a shift shock due to sudden engagement of the combined device. In particular, since the intermediate correction control value GD is learned and corrected based on the actual shift state, the shift shock is appropriately suppressed regardless of individual differences (variations) of various components, deterioration over time of friction materials, lubricants, and the like. it can.
[0047]
Further, since the intermediate correction control value GD is learned and corrected based on the gradient ΔNT2 of the turbine rotation speed NT after the correction by the engagement force intermediate correction means 108 and before the end of the shift, the change speed of the turbine rotation speed NT. It is possible to more effectively suppress a shift shock such as a change in driving torque at the time of complete engagement, which is greatly influenced by. That is, if the crossing angle between the turbine rotational speed NT and the rear gear stage rotational speed NTUP is large, torque fluctuation is likely to occur as shown by the broken line in the column of the output shaft torque in FIG. It is desirable to perform hydraulic control so as to smoothly intersect the speed NTUP.
[0048]
In this embodiment, the constant pressure standby pressure control value DSL1 at the start of the upshift is changed._BIs corrected by learning based on the turbine rotational speed gradient ΔNT1 in the first half of the shift, and the constant pressure standby pressure control value DSL1 is corrected._BSince the learning correction of the intermediate correction control value GD is performed on the assumption that the learning correction is in the convergence state, the constant pressure standby pressure control value DSL1_BThis prevents the learning correction accuracy of the intermediate correction control value GD from being impaired or hunting from occurring due to the influence of the learning correction. In particular, the constant pressure standby pressure control value DSL1_BMeasurement region (time t) of turbine rotational speed gradient ΔNT1 involved in learning correction of₂~ T_Three) And the measurement region (time t) of the turbine rotational speed gradient ΔNT2 involved in learning correction of the intermediate correction control value GD_Four~ T_Five) Are not overlapped with each other, so that interference between both learning corrections is reduced.
[0049]
As mentioned above, although the Example of this invention was described in detail based on drawing, this is an embodiment to the last, and this invention implements in the aspect which added various change and improvement based on the knowledge of those skilled in the art. Can do.
[Brief description of the drawings]
FIG. 1 is a skeleton diagram illustrating a configuration of a vehicle drive device to which the present invention is applied.
FIG. 2 is a diagram illustrating an engagement operation of a clutch and a brake for establishing each gear stage of the automatic transmission of FIG.
3 is a block diagram illustrating a control system that performs engine control and shift control of the vehicle drive device of FIG. 1; FIG.
4 is a diagram illustrating an example of a shift pattern of the shift lever of FIG. 3; FIG.
5 is an accelerator pedal operation amount A used in throttle control performed by the electronic control unit of FIG. 3;_CCAnd throttle valve opening θ_THFIG.
6 is a diagram showing an example of a shift map used in shift control of an automatic transmission performed by the electronic control unit of FIG. 3. FIG.
7 is a block diagram illustrating functions related to engagement force control of the engagement side frictional engagement device during upshifting executed by the electronic control unit of FIG. 3; FIG.
FIG. 8 is a flowchart for specifically explaining the contents of signal processing by the engagement force intermediate correction unit and the intermediate correction value learning correction unit of FIG. 7;
FIG. 9 is an example of a time chart showing changes in the operating state of each part during a 3 → 4 upshift.
[Explanation of symbols]
14: Automatic transmission 90: Electronic control unit 98: Hydraulic control circuit 100: Engagement force control means 108: Engagement force intermediate correction means 112: Initial engagement force learning correction means 114: Intermediate correction value learning correction means (intermediate correction learning correction means GD: Intermediate correction control value (intermediate correction value) DSL1_B: Constant pressure standby pressure control value (initial engagement force) NT: Turbine rotational speed (automatic transmission input rotational speed) P_B1: Hydraulic pressure (engagement force)

Claims (2)

An automatic transmission in which a plurality of gear stages having different gear ratios according to engagement and disengagement states of the friction engagement device are established;
Engagement force control means for controlling the engagement force of the friction engagement device at the time of an upshift in which a predetermined friction engagement device is engaged to shift to a gear stage having a small gear ratio;
In a vehicle shift control device having
Initial engagement force learning correction means for changing the initial engagement force of the friction engagement device controlled by the engagement force control means at the start of shifting of the upshift based on an actual shift state;
Engagement force intermediate correction means for correcting the engagement force of the friction engagement device controlled by the engagement force control means during a shift in which the change in the input rotation speed in the inertia phase of the upshift has progressed by 50% or more;
With the learning permission condition that the change in the initial engagement force by the initial engagement force learning correction unit is in a convergent state, an intermediate correction value or correction duration time that is a correction amount of the engagement force by the engagement force intermediate correction unit, Intermediate correction learning correction means for changing based on the actual shift state;
A shift control apparatus for a vehicle, comprising: The intermediate correction learning correction means changes the intermediate correction value or the correction continuation time based on a change in the input rotational speed of the automatic transmission after the correction by the engagement force intermediate correction means and before the end of the shift. The vehicle shift control device according to claim 1, wherein

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